Every man sins. But we are talking about something deliberate, habitual, and ONGOING.
A person that CHOOSES to CONTINUE in a bad path is not living in the 1 John 3:2-3 principle, is he?
And the rest of 1 John 3 indicates that if such a pattern is ONGOING and habitual, that person likely has never been saved.
Read the rest of 1 John 3